There is growing frustration in Haiti at delays in aid reaching the island in the aftermath of Tuesday's devastating earthquake.

Shaul Schwarz, a photographer for TIME magazine, gave today's programme a graphic description of a roadblock built from corpses built in one part of Port-au-Prince by residents to protest at the delay in emergency aid reaching them.

Interviewed by presenter John Humphrys, Lord Mark Malloch-Brown, the former British foreign office minister and former UN Deputy Secretary-General, said that, although the delay was "longer than people would ideally want", it would begin to flow much freely very soon.

"The UN is in a better place to regroup and recover" than in places where it doesn't have an on going presence, he added.

Casualty figures are still vague but up to 50,000 people are believed to have died following the earthquake.